Firmware v 2.1, several bug fixes

Thanks to William Phelps - wm (at) usa.net, for several important bug
fixes.    https://github.com/wbphelps/AlphaClock

* Alarm can now be turned off while snoozing
* Day/month adjust from within menu had unpredictable behavior around
certain month/year boundaries.
* Reorganized library into separate .h/.c files
* Renamed default firmware example sketch
* Tested with Arduino 1.0.3.
update readme
Merge branch 'master' of https://github.com/oskay/AlphaClock into Master
rename Alpha_20_ino -> defaultfirmware
Merge branch 'master' into WmFixes
Merge branch 'WmFixes' into WmChanges
Merge latest "WmFixes" into "WmChanges"